Health Effects & Risks

What we know

  • Zika virus disease is generally mild, and severe disease requiring hospitalization and deaths are uncommon.
  • Zika infection during pregnancy can cause serious birth defects and is associated with other pregnancy problems.
  • Rarely, Zika may cause Guillain-Barré syndrome, an uncommon sickness of the nervous system in which a person’s own immune system damages the nerve cells, causing muscle weakness, and sometimes, paralysis.
  • Very rarely, Zika may cause severe disease affecting the brain, causing swelling of the brain or spinal cord or a blood disorder which can result in bleeding, bruising or slow blood clotting.

Graphic of doctor with a patient